Integrated drilling wellbore pressure control method

Abstract

The present invention relates to the technical field of bottom hole pressure control methods for the oil and gas drilling industry, and is an integrated drilling wellbore pressure control method, which is performed according to the following steps: presetting the bottom hole pressure of the pressure-controlled drilling by a design module; collecting real-time data of the working condition conversion of the pressure-controlled drilling manifold by a data acquisition module, and transmitting it to a hydraulic calculation module; the hydraulic calculation module calculates the pressure-controlled drilling wellhead pressure according to the pressure-controlled drilling bottom hole pressure pre-set by the design module, the real-time data collected by the data acquisition module, and the non-real-time data input in the early stage, and outputs it to the control module; the control module sends an electric control signal according to the calculated pressure-controlled drilling wellhead pressure. The present invention forms a set of pressure-controlled drilling wellbore pressure control methods that integrate riser diversion and throttling control through module control, realizes accurate control of wellbore pressure under various working conditions of pressure-controlled drilling, reduces wellbore pressure fluctuations, and maintains bottom hole pressure stability.

Description

Technical Field

[0001] The invention relates to the technical field of bottom hole pressure control methods for oil and gas drilling industries, and is an integrated drilling wellbore pressure control method. Background Art

[0002] Managed pressure drilling is the development direction of new drilling technologies in recent years. Through continuous control of the wellbore pressure profile, this technology can effectively reduce the wellbore pressure fluctuations caused by process conversions such as stopping and starting pumps in conventional drilling, thereby achieving safe drilling in formations with narrow pressure windows. In recent years, it has achieved good application results in deep well and horizontal well drilling.

[0003] The existing fine pressure-controlled drilling system adopts a skid-mounted combination of an automatic throttling manifold and a separate back-pressure compensation pump. This has the disadvantages of occupying a large area and requiring explosion-proofing of the compensation pump near the wellhead, which poses great challenges to on-site installation and meeting safety and environmental protection requirements.

[0004] In response to the above problems, the Western Drilling Engineering and Technology Research Institute has developed a fine pressure controlled drilling system that integrates back pressure compensation and throttling control, and can simultaneously and accurately measure the inlet and outlet flow rates. It has also carried out intelligent decision-making analysis software development and supporting process technology research to achieve remote monitoring and decision-making, continuously improve the performance of the fine pressure controlled drilling system, and provide technical support for safe drilling in complex deep wells and narrow density window formations. Summary of the invention

[0005] The present invention provides an integrated drilling wellbore pressure control method, which overcomes the deficiencies of the above-mentioned prior art and provides an integrated drilling wellbore pressure control method to achieve stable control of bottom hole pressure.

[0006] The technical solution of the present invention is achieved through the following measures: an integrated drilling wellbore pressure control method is carried out according to the following steps: the first step is to pre-set the pressure-controlled drilling bottomhole pressure through the design module; the second step is to collect the real-time data of the pressure-controlled drilling manifold working condition conversion by the data acquisition module, and transmit the collected real-time data to the hydraulic calculation module, wherein the real-time data of the pressure-controlled drilling manifold working condition conversion includes pressure, flow, gate valve switch state and throttle valve opening; the third step is that the hydraulic calculation module calculates the pressure-controlled drilling wellhead pressure according to the pressure-controlled drilling bottomhole pressure pre-set by the design module, the real-time data collected by the data acquisition module and the non-real-time data input in the early stage, and outputs it to the control module; the fourth step is that the control module sends an electrical control signal according to the calculated pressure-controlled drilling wellhead pressure, and the electrical control signal includes a throttle valve control signal and a gate valve control signal.

[0007] The following is a further optimization and / or improvement of one of the above-mentioned technical solutions:

[0008] In the above second step, the managed pressure drilling manifold includes a throttling part and a riser diversion part, the throttling part consists of a first throttling passage, a second throttling passage and a third throttling passage, and the riser diversion part consists of a riser passage and a diversion passage.

[0009] In the above second step, the operating conditions of the managed pressure drilling manifold include the managed pressure drilling procedure, the managed pressure pump stop procedure, the managed pressure pump start procedure, the managed pressure drilling and heavy grout cap replacement procedure, the heavy grout cap replacement and managed pressure drilling procedure.

[0010] The process of the above-mentioned controlled pressure drilling procedure is as follows: the drilling fluid is pumped out by the drilling pump and enters the riser through the riser passage in the riser diversion part, and the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part, and passes through the throttling valve and outlet flow meter of the first throttling passage and the second throttling passage in the throttling part to meet the preset bottom hole pressure of the design module and maintain the stability of the bottom hole pressure.

[0011] The process of the above-mentioned pressure control pump stop program is: gradually open the bypass passage in the riser bypass part, close the riser passage in the riser bypass part, pour the riser passage in the riser bypass part to the bypass passage, connect it with the throttling part, and simultaneously operate the throttling valves of the first throttling passage and the second throttling passage in the throttling part to complete the wellhead pressure adjustment calculated by the hydraulic calculation module, meet the preset bottom hole pressure of the design module, and maintain the stability of the bottom hole pressure.

[0012] The riser passage in the riser shunt part is opened, the shunt passage in the riser shunt part is gradually closed, the shunt passage in the riser shunt part is poured into the riser passage, and the throttle valves of the first throttle passage and the second throttle passage in the throttling part are adjusted according to the wellhead pressure calculated by the hydraulic calculation module, and the bottom hole pressure preset by the pressure controlled drilling state design module is restored to maintain the bottom hole pressure stable.

[0013] The process of the above-mentioned controlled pressure drilling and heavy slurry cap replacement program is as follows: after the well is evenly washed by circulation, the riser passage in the riser diversion part is reversed to the diversion passage according to the controlled pressure pump stop program, and connected with the first throttling passage and the second throttling passage in the throttling part, and the throttle valves of the first throttling passage and the second throttling passage in the throttling part are operated to complete the wellhead pressure adjustment calculated by the hydraulic calculation module, control the wellhead casing pressure to start drilling to the predetermined well depth, meet the preset bottom hole pressure of the design module, maintain the stability of the bottom hole pressure, and then According to the pressure-controlled pump-starting procedure, the bypass passage in the riser bypass part is poured back to the riser passage, and the circulation passage in the pressure-controlled drilling procedure is restored. According to the annular pressure loss calculated according to the well depth, the throttle valve and outlet flow meter of the first throttle passage and the second throttle passage in the flow part are used to control the wellhead casing pressure and pump in heavy drilling fluid from the drilling pump. According to the height of the pumped heavy drilling fluid in the wellbore annulus, the wellhead casing pressure and the drilling pump displacement are gradually reduced. After the heavy drilling fluid is replaced, the pump is stopped and the bottom hole pressure is stabilized within the set target.

[0014] The above-mentioned process of replacing the heavy slurry cap and controlling the pressure to drill down is as follows: conventionally drill down to the bottom of the heavy slurry cap, adjust to the circulation path in the controlled pressure drilling program, start the drilling pump according to the set displacement, gradually replace the heavy drilling fluid in the wellbore with the wellbore, gradually increase the drilling pump displacement and the wellhead casing pressure according to the replacement height of the heavy drilling fluid in the wellbore, maintain the bottom hole pressure stable within the set target, wait for the heavy drilling fluid in the wellbore to be completely replaced, and according to the pressure control pump stop procedure, reverse the riser passage in the riser diversion part to the diversion passage, connect it with the first throttling passage and the second throttling passage in the throttling part, operate the throttling valves of the first throttling passage and the second throttling passage in the throttling part, control the wellhead casing pressure to drill down to the bottom of the well, and maintain the bottom hole pressure stable within the set target.

[0015] The circulation path in the above-mentioned controlled pressure drilling procedure is that the drilling fluid comes out of the drilling pump and enters the riser through the riser path in the riser diversion part, and the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part.

[0016] The present invention forms a wellbore pressure control method for controlled pressure drilling that integrates riser diversion and throttling control through module control, thereby achieving precise control of wellbore pressure under various working conditions of controlled pressure drilling, reducing wellbore pressure fluctuations, and maintaining stable bottom hole pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 It is a schematic diagram of the process flow of the present invention.

[0018] Attached Figure 2 It is a schematic diagram of the structure of the managed pressure drilling manifold in the present invention.

[0019] The codes in the attached drawings are: 1 for the inlet five-way valve, 2 for the hydraulic gate valve, 3 for the throttle valve, 4 for the outlet five-way valve, 5 for the manual gate valve, 6 for the first four-way valve, 7 for the filter four-way valve, 8 for the mass flow meter, 9 for the inlet filter four-way valve, 10 for the pressure relief gate valve, 11 for the high-pressure mass flow meter, 12 for the long four-way valve, 13 for the second four-way valve, 14 for the third four-way valve, 15 for the fifteenth pipeline, 16 for the first pipeline, 17 for the second pipeline, 18 for the third pipeline, 19 for the fourth pipeline, 20 for the fifth pipeline, 21 for the sixth pipeline, 22 for the seventh pipeline, 23 for the eighth pipeline, 24 for the ninth pipeline, 25 for the tenth pipeline, 26 for the eleventh pipeline, 27 for the twelfth pipeline, 28 for the thirteenth pipeline, 29 for the fourteenth pipeline, and 30 for the sixteenth pipeline. DETAILED DESCRIPTION

[0020] The present invention is not limited by the following embodiments, and specific implementation methods can be determined based on the technical solution of the present invention and actual conditions.

[0021] The present invention will be further described below in conjunction with embodiments:

[0022] Embodiment 1: As attached Figure 1 As shown, the integrated drilling wellbore pressure control method is carried out according to the following steps: the first step is to pre-set the pressure-controlled drilling bottomhole pressure through the design module; the second step is to collect the real-time data of the pressure-controlled drilling manifold working condition conversion by the data acquisition module, and transmit the collected real-time data to the hydraulic calculation module, wherein the real-time data of the pressure-controlled drilling manifold working condition conversion includes pressure, flow, gate valve switch state and throttle valve opening; the third step is that the hydraulic calculation module calculates the pressure-controlled drilling wellhead pressure according to the pressure-controlled drilling bottomhole pressure pre-set by the design module, the real-time data collected by the data acquisition module and the non-real-time data input in the early stage, and outputs it to the control module; the fourth step is that the control module sends an electric control signal according to the calculated pressure-controlled drilling wellhead pressure, and the electric control signal includes a throttle valve control signal and a gate valve control signal.

[0023] The present invention forms a set of pressure-controlled drilling wellbore pressure control method integrating riser diversion and throttling control through design module, data acquisition module, hydraulic calculation module and control module, which improves the control accuracy of wellbore pressure, reduces wellbore pressure fluctuation and maintains bottom hole pressure stability. Among them, the hydraulic calculation module adopts the existing known MPD pressure control decision analysis system developed by Beijing Yiheng Sunshine Technology Development Co., Ltd. for analysis and calculation.

[0024] Embodiment 2: As an optimization of the above embodiment, in the second step, the pressure-controlled drilling manifold includes a throttling part and a riser diversion part, the throttling part is composed of a first throttling passage, a second throttling passage and a third throttling passage, and the riser diversion part is composed of a riser passage and a diversion passage.

[0025] In the present invention, as shown in the attached Figure 2As shown, in the pressure-controlled drilling manifold, the throttling part includes an inlet five-way 1, an automatic outlet five-way 4, a filtering four-way 7, and a first four-way 6. The left inlet of the inlet five-way 1 is fixedly connected with a first pipeline 16, the right end of the inlet five-way 1 and the left inlet of the automatic outlet five-way 4 are fixedly connected with a second pipeline 17, the top first outlet of the inlet five-way 1 and the top first inlet of the automatic outlet five-way 4 are fixedly connected with a fourth pipeline 19, the top second outlet of the inlet five-way 1 and the top second inlet of the automatic outlet five-way 4 are fixedly connected with a third pipeline 18, the right outlet of the automatic outlet five-way 4 and the left inlet of the filtering four-way 7 are fixedly connected with a fifth pipeline 20, and the top outlet of the filtering four-way 7 is fixedly connected with a fifth pipeline 21. A sixth pipeline 21 is fixedly connected between the inlet and the top inlet of the first four-way 6, a seventh pipeline 22 is fixedly connected between the right end outlet of the filtering four-way 7 and the left end inlet of the first four-way 6, a sixteenth pipeline 30 is fixedly connected to the left end outlet of the first four-way 6, the riser flow diversion part includes the second four-way 13, the third four-way 14, the long four-way 12, and the inlet filtering four-way 9, an eighth pipeline 23 is fixedly connected between the bottom outlet of the inlet five-way 1 and the top inlet of the second four-way 13, a tenth pipeline 25 is fixedly connected to the left end outlet of the third four-way 14, an eleventh pipeline 26 is fixedly connected between the right end inlet of the third four-way 14 and the left end outlet of the long four-way 12, and the first inlet at the bottom of the long four-way 12 is fixedly connected. A ninth pipeline 24 is fixedly connected between the right end outlet of the second four-way 13 and the long four-way 12, a thirteenth pipeline 28 is fixedly connected between the right end inlet of the long four-way 12 and the left end outlet of the inlet filter four-way 9, a twelfth pipeline 27 is fixedly connected between the second inlet at the bottom end of the long four-way 12 and the bottom outlet of the inlet filter four-way 9, a fourteenth pipeline 29 is fixedly connected to the right end inlet of the inlet filter four-way 9, a fifteenth pipeline 15 is fixedly connected between the bottom outlet of the automatic outlet five-way 4 and the top inlet of the third four-way 14, a hydraulic gate valve 2, an automatic throttle valve 3 and a manual gate valve 5 are connected in series in sequence on the fourth pipeline 19, and a hydraulic gate valve 2, an automatic throttle valve 3 and a manual gate valve 5 are connected in series in sequence on the third pipeline 18 3 and a manual gate valve 5, the second pipeline 17 is connected in series with a manual gate valve 5, the second pipeline 17 is connected in series with a manual gate valve 5, the sixth pipeline 21 is connected in series with a manual gate valve 5, a mass flowmeter 8 and a manual gate valve 5, the seventh pipeline 22 is connected in series with a manual gate valve 5, the ninth pipeline 24 is connected in series with a manual gate valve 5, an automatic throttle valve 3 and a hydraulic gate valve 2, the twelfth pipeline 27 is connected in series with a manual gate valve 5, a high-pressure mass flowmeter 11 and a manual gate valve 5, the eleventh pipeline 26 is connected in series with a hydraulic gate valve 2, the thirteenth pipeline 28 is connected in series with a manual gate valve 5, and the fifteenth pipeline 15 is connected in series with a pressure relief gate valve 10.

[0026] Among them, the first throttling path is: first pipeline 16 → inlet five-way 1 → fourth pipeline 19 → hydraulic gate valve 2 → throttle valve 3 → manual gate valve 5 → outlet five-way 4;

[0027] The second throttling path is: first pipeline 16 → inlet five-way valve 1 → third pipeline 18 → hydraulic gate valve 2 → throttle valve 3 → manual gate valve 5 → outlet five-way valve 4;

[0028] The third throttling path is: first pipeline 16 → inlet five-way valve 1 → second pipeline 17 → manual gate valve 5 → outlet five-way valve 4;

[0029] The riser passage is: the fourteenth pipeline 29 → three-way 9 → manual gate valve 5 → high-pressure mass flowmeter 11 → the twelfth pipeline 27 → manual gate valve 5 → long four-way 12 → the eleventh pipeline 26 → hydraulic gate valve 2 → the third four-way 14 → the tenth pipeline 25;

[0030] The shunt passage is: the fourteenth pipeline 29 → three-way 9 → manual gate valve 5 → high-pressure mass flowmeter 11 → the twelfth pipeline 27 → manual gate valve 5 → long four-way 12 → hydraulic gate valve 2 → throttle valve 3 → ninth pipeline → manual gate valve 5 → second four-way 13 → inlet five-way 1.

[0031] Embodiment 3: As an optimization of the above embodiment, in the second step, the pressure-controlled drilling manifold working conditions include pressure-controlled drilling procedure, pressure-controlled pump stop procedure, pressure-controlled pump start procedure, pressure-controlled drilling and heavy grouting cap replacement procedure, heavy grouting cap replacement and pressure-controlled drilling procedure.

[0032] Embodiment 4: As attached Figure 2 As shown, as an optimization of the above embodiment, the process of the controlled pressure drilling program is as follows: the drilling fluid is pumped out by the drilling pump and enters the riser through the riser passage in the riser diversion part, the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part, and passes through the throttling valve 3 and the outlet flow meter 11 of the first throttling passage and the second throttling passage in the throttling part to meet the preset bottom hole pressure of the design module and maintain the stability of the bottom hole pressure.

[0033] Embodiment 5: As attached Figure 2 As shown, as an optimization of the above embodiment, the process of the pressure control pump stop program is: gradually open the shunt passage in the riser shunt part (open the hydraulic gate valve 2 and the throttle valve 3 on the passage), close the riser passage in the riser shunt part (close the hydraulic gate valve 2 on the passage), pour the riser passage in the riser shunt part to the shunt passage, connect it with the throttling part, and operate the throttle valve 3 of the first throttle passage and the second throttle passage in the throttling part at the same time, complete the wellhead pressure adjustment calculated by the hydraulic calculation module, meet the preset bottom hole pressure of the design module, and maintain the stability of the bottom hole pressure.

[0034] Embodiment 6: As attached Figure 2As shown, as an optimization of the above embodiment, the process of the pressure-controlled pump-on program is: open the riser passage in the riser shunt part (open the hydraulic gate valve 2 on the passage), gradually close the shunt passage in the riser shunt part (close the hydraulic gate valve 2 and the throttle valve 3 on the passage), pour the shunt passage in the riser shunt part to the riser passage, adjust the throttle valve 3 of the first throttle passage and the second throttle passage in the throttling part according to the wellhead pressure calculated by the hydraulic calculation module, restore the preset bottom hole pressure of the pressure-controlled drilling state design module, and maintain the bottom hole pressure stable.

[0035] Embodiment 7: As attached Figure 2 As shown, as an optimization of the above embodiment, the process of the pressure-controlled drilling and heavy slurry cap replacement program is as follows: after the well is evenly washed by circulation, the riser passage in the riser shunt part is reversed to the shunt passage according to the pressure-controlled pump stop program, and connected with the first throttling passage and the second throttling passage in the throttling part, and the throttling valve 3 of the first throttling passage and the second throttling passage in the throttling part is operated to complete the wellhead pressure adjustment calculated by the hydraulic calculation module, control the wellhead casing pressure to start drilling to a predetermined well depth, meet the bottom hole pressure preset by the design module, and maintain the bottom hole pressure After the wellbore is stabilized, the bypass passage in the riser bypass part is returned to the riser passage according to the pressure control pump start procedure, and the circulation passage in the pressure control drilling procedure is restored. According to the annular space pressure loss calculated according to the well depth, the throttle valve 3 and the outlet flow meter 11 of the first throttle passage and the second throttle passage in the flow part are used to control the wellhead casing pressure and pump heavy drilling fluid from the drilling pump. According to the height of the pumped heavy drilling fluid in the wellbore annulus, the wellhead casing pressure and the drilling pump displacement are gradually reduced. After the heavy drilling fluid is replaced, the pump is stopped and the bottom hole pressure is stabilized within the set target.

[0036] Embodiment 8: As attached Figure 2 As shown, as an optimization of the above embodiment, the process of replacing the heavy slurry cap and the pressure-controlled drilling procedure is: conventionally drill down to the bottom of the heavy slurry cap, adjust to the circulation path in the pressure-controlled drilling program, start the drilling pump according to the set displacement, gradually replace the heavy drilling fluid in the wellbore with the wellbore, gradually increase the drilling pump displacement and the wellhead casing pressure according to the replacement height of the heavy drilling fluid in the wellbore, maintain the bottom hole pressure stable within the set target, wait for the heavy drilling fluid in the wellbore to be completely replaced, according to the pressure-controlled pump stop procedure, the riser passage in the riser shunt part is reversed to the shunt passage, connected with the first throttling passage and the second throttling passage in the throttling part, operate the throttling valve 3 of the first throttling passage and the second throttling passage in the throttling part, control the wellhead casing pressure to drill to the bottom of the well, and maintain the bottom hole pressure stable within the set target.

[0037] In actual production needs, the present invention drills down to the bottom of the well, and according to the pressure-controlled pump-starting procedure, the shunt passage in the riser shunt part is reversed to the riser passage, the circulation passage in the pressure-controlled drilling procedure is restored, and the pressure-controlled drilling procedure is restored.

[0038] Embodiment 9: As an optimization of the above embodiment, the circulation path in the controlled pressure drilling program is that the drilling fluid comes out of the drilling pump and enters the riser through the riser path in the riser diversion part, and the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part.

[0039] In the present invention, in addition to completing the functions of the controlled pressure drilling program, the controlled pressure pump start program, the controlled pressure pump stop program, the controlled pressure drilling and the heavy grouting cap replacement program, the heavy grouting cap replacement and the controlled pressure drilling program, the controlled pressure circulation density reduction / increase, the controlled pressure casing and the controlled pressure cementing functions can also be completed, and the operation is similar to the above-mentioned functions. At the same time, in addition to the automatic throttling control, the above program can also perform manual throttling control.

[0040] In summary, the present invention forms a wellbore pressure control method for controlled pressure drilling that integrates riser diversion and throttling control through module control, thereby achieving precise control of wellbore pressure under various working conditions of controlled pressure drilling, reducing wellbore pressure fluctuations, and maintaining stable bottom hole pressure.

[0041] The above technical features constitute the embodiments of the present invention, which have strong adaptability and implementation effect. Non-essential technical features can be added or reduced according to actual needs to meet the requirements of different situations.

Claims

1. An integrated drilling wellbore pressure control method, characterized in that Follow the steps below: The first step is to pre-set the bottom hole pressure of the managed pressure drilling through the design module; In the second step, the data acquisition module collects the real-time data of the working condition conversion of the pressure-controlled drilling manifold, and transmits the collected real-time data to the hydraulic calculation module, wherein the real-time data of the working condition conversion of the pressure-controlled drilling manifold includes pressure, flow, gate valve switch status and throttle valve opening, the pressure-controlled drilling manifold includes a throttling part and a riser diversion part, the throttling part consists of a first throttling passage, a second throttling passage and a third throttling passage, the riser diversion part consists of a riser passage and a diversion passage, the working conditions of the pressure-controlled drilling manifold include a pressure-controlled drilling program, a pressure-controlled pump stop program, a pressure-controlled pump start program, a pressure-controlled drilling and heavy slurry cap replacement program, a heavy slurry cap replacement and a pressure-controlled drilling program, The process of the controlled pressure drilling procedure is as follows: the drilling fluid is pumped out by the drilling pump and enters the riser through the riser passage in the riser diversion part; the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part; and passes through the throttling valve and outlet flow meter of the first throttling passage and the second throttling passage in the throttling part to meet the bottom hole pressure preset by the design module and maintain the stability of the bottom hole pressure. The process of the pressure control pump stop program is: gradually opening the shunt passage in the riser shunt part, closing the riser passage in the riser shunt part, pouring the riser passage in the riser shunt part to the shunt passage, connecting it with the throttling part, and operating the throttle valves of the first throttling passage and the second throttling passage in the throttling part at the same time, completing the wellhead pressure adjustment calculated by the hydraulic calculation module, meeting the preset bottom hole pressure of the design module, and maintaining the stability of the bottom hole pressure, The process of the pressure-controlled pump-on procedure is as follows: opening the riser passage in the riser shunt part, gradually closing the shunt passage in the riser shunt part, pouring the shunt passage in the riser shunt part into the riser passage, adjusting the throttle valves of the first throttle passage and the second throttle passage in the throttling part according to the wellhead pressure calculated by the hydraulic calculation module, restoring the bottom hole pressure preset by the pressure-controlled drilling state design module, and maintaining the bottom hole pressure stable. The process of the pressure-controlled drilling and heavy slurry cap replacement program is as follows: after the well is evenly washed by circulation, the riser passage in the riser shunt part is reversed to the shunt passage according to the pressure-controlled pump stop program, and connected with the first throttling passage and the second throttling passage in the throttling part, the throttling valves of the first throttling passage and the second throttling passage in the throttling part are operated, the wellhead pressure adjustment calculated by the hydraulic calculation module is completed, the wellhead casing pressure is controlled to start drilling to a predetermined well depth, the bottom hole pressure preset by the design module is met, and the bottom hole pressure is maintained stable, and then According to the pressure control pump start procedure, the bypass passage in the riser bypass part is returned to the riser passage, and the circulation passage in the pressure control drilling procedure is restored. According to the annular pressure loss calculated according to the well depth, the throttle valve and outlet flow meter of the first throttle passage and the second throttle passage in the flow part are used to control the wellhead casing pressure and pump heavy drilling fluid from the drilling pump. According to the height of the pumped heavy drilling fluid in the wellbore annulus, the wellhead casing pressure and the drilling pump displacement are gradually reduced. After the heavy drilling fluid is replaced, the pump is stopped, and the bottom hole pressure is stabilized within the set target. The process of replacing the heavy slurry cap and the controlled pressure drilling procedure is as follows: conventionally drill down to the bottom of the heavy slurry cap, adjust to the circulation path in the controlled pressure drilling procedure, start the drilling pump according to the set displacement, gradually replace the heavy drilling fluid in the wellbore with the wellbore, gradually increase the drilling pump displacement and the wellhead casing pressure according to the replacement height of the heavy drilling fluid in the wellbore, maintain the bottom hole pressure stable within the set target, wait for the heavy drilling fluid in the wellbore to be completely replaced, and according to the controlled pressure pump stop procedure, reverse the riser passage in the riser shunt part to the shunt passage, connect with the first throttling passage and the second throttling passage in the throttling part, operate the throttling valves of the first throttling passage and the second throttling passage in the throttling part, control the wellhead casing pressure to drill down to the bottom of the well, and maintain the bottom hole pressure stable within the set target; In the third step, the hydraulic calculation module calculates the wellhead pressure of the controlled pressure drilling according to the bottom hole pressure of the controlled pressure drilling preset by the design module, the real-time data collected by the data acquisition module and the non-real-time data input in the early stage, and outputs it to the control module; In the fourth step, the control module sends out an electric control signal according to the calculated pressure-controlled drilling wellhead pressure, and the electric control signal includes a throttle valve control signal and a gate valve control signal.

2. The integrated drilling wellbore pressure control method according to claim 1, characterized in that The circulation path in the managed pressure drilling program is that the drilling fluid comes out of the drilling pump and enters the riser through the riser path in the riser diversion part, and the drilling fluid returned from the wellbore annulus returns to the drilling fluid tank through the inlet and outlet of the throttling part.

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